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        <h2>
          <span class="refentrytitle">zkwm</span>
        </h2>
        <p>zkwm — 
      Writes to a zk variable at k-rate with mixing.
          </p>
      </div>
      <div class="refsect1">
        <a id="idp170235856"></a>
        <h2>Description</h2>
        <p>
      Writes to a zk variable at k-rate with mixing.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp170237200"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>zkwm</strong></span> ksig, kndx [, imix]</pre>
      </div>
      <div class="refsect1">
        <a id="idp170239280"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>imix</em></span> (optional, default=1) -- indicates if mixing should occur.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp170241056"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>ksig</em></span> -- value to be written to the zk location.
    </p>
        <p>
      <span class="emphasis"><em>kndx</em></span> -- points to the zk or za location to which to write.
    </p>
        <p>
      <span class="emphasis"><em>zkwm</em></span> is a mixing opcode, it adds the signal to the current value of the variable. If no <span class="emphasis"><em>imix</em></span> is specified, mixing always occurs. <span class="emphasis"><em>imix</em></span> = 0 will cause overwriting like <span class="emphasis"><em>ziw</em></span>, <span class="emphasis"><em>zkw</em></span>, and <span class="emphasis"><em>zaw</em></span>. Any other value will cause mixing.
    </p>
        <p>
      <span class="emphasis"><em>Caution</em></span>: When using the mixing opcodes <span class="emphasis"><em>ziwm</em></span>, <span class="emphasis"><em>zkwm</em></span>, and <span class="emphasis"><em>zawm</em></span>, care must be taken that the variables mixed to, are zeroed at the end (or start) of each k- or a-cycle. Continuing to add signals to them, can cause their values can drift to astronomical figures.
    </p>
        <p>
      One approach would be to establish certain ranges of zk or za variables to be used for mixing, then use <span class="emphasis"><em>zkcl</em></span> or <span class="emphasis"><em>zacl</em></span> to clear those ranges.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp170310544"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the zkwm opcode. It uses the file <a class="ulink" href="examples/zkwm.csd" target="_top"><em class="citetitle">zkwm.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp170312320"></a>
          <p class="title">
            <strong>Example 1075. Example of the zkwm opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out   Audio in    No messages</span>
-odac           -iadc     -d     <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o zkwm.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="comment">; Initialize the ZAK space.</span>
<span class="comment">; Create 1 a-rate variable and 1 k-rate variable.</span>
<span class="opc">zakinit</span> 1, 1

<span class="comment">; Instrument #1 -- a basic instrument.</span>
<span class="oblock">instr</span> 1
  <span class="comment">; Generate a k-rate signal.</span>
  <span class="comment">; The signal goes from 30 to 20,000 then back to 30.</span>
  kramp <span class="opc">linseg</span> 30, p3<span class="op">/</span>2, 20000, p3<span class="op">/</span>2, 30

  <span class="comment">; Mix the signal into the zk variable #1.</span>
  <span class="opc">zkwm</span> kramp, 1
<span class="oblock">endin</span>

<span class="comment">; Instrument #2 -- another basic instrument.</span>
<span class="oblock">instr</span> 2
  <span class="comment">; Generate another k-rate signal.</span>
  <span class="comment">; This is a low frequency oscillator.</span>
  klfo <span class="opc">lfo</span> 3500, 2

  <span class="comment">; Mix this signal into the zk variable #1.</span>
  <span class="opc">zkwm</span> klfo, 1
<span class="oblock">endin</span>

<span class="comment">; Instrument #3 -- generates audio output.</span>
<span class="oblock">instr</span> 3
  <span class="comment">; Read zk variable #1, containing a mix of both signals.</span>
  kamp <span class="opc">zkr</span> 1

  <span class="comment">; Create a sine waveform. Its amplitude will vary</span>
  <span class="comment">; according to the values in zk variable #1.</span>
  a1 <span class="opc">oscil</span> kamp, 880, 1

  <span class="comment">; Generate the audio output.</span>
  <span class="opc">out</span> a1

  <span class="comment">; Clear the zk variable, get it ready for </span>
  <span class="comment">; another pass.</span>
  <span class="opc">zkcl</span> 0, 1
<span class="oblock">endin</span>


<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Table #1, a sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="comment">; Play Instrument #1 for 5 seconds.</span>
<span class="stamnt">i</span> 1 0 5
<span class="comment">; Play Instrument #2 for 5 seconds.</span>
<span class="stamnt">i</span> 2 0 5
<span class="comment">; Play Instrument #3 for 5 seconds.</span>
<span class="stamnt">i</span> 3 0 5
<span class="stamnt">e</span>


<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp170316576"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="zaw.html" title="zaw"><em class="citetitle">zaw</em></a>,
      <a class="link" href="zawm.html" title="zawm"><em class="citetitle">zawm</em></a>,
      <a class="link" href="ziw.html" title="ziw"><em class="citetitle">ziw</em></a>,
      <a class="link" href="ziwm.html" title="ziwm"><em class="citetitle">ziwm</em></a>,
      <a class="link" href="zkcl.html" title="zkcl"><em class="citetitle">zkcl</em></a>,
      <a class="link" href="zkw.html" title="zkw"><em class="citetitle">zkw</em></a>,
      <a class="link" href="zkr.html" title="zkr"><em class="citetitle">zkr</em></a>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp170324192"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: Robin Whittle</td>
          </tr>
          <tr>
            <td>Australia</td>
          </tr>
          <tr>
            <td>May 1997</td>
          </tr>
        </table>
        <p>
    </p>
        <p>New in version 3.45</p>
        <p>Example written by Kevin Conder.</p>
      </div>
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